K-01 Summary

Pentax goes its own way with a mirrorless camera that accepts standard K-mount lenses. That means access to a huge back catalog of quality optics without an adapter. Unfortunately, it also necessitates a body that's barely any smaller than a standard SLR.

Barely any smaller than a standard SLR, but lacks viewfinder and phase-detect autofocus. Contrast-detect AF is slow and unreliable. Body design is clumsy and uncomfortable. Very slow raw burst shooting.

Price and availability

The Pentax K-01 shipped in the US market from March 2012. Pricing is set at around US$750 body-only, or US$900 in a kit with the new smc PENTAX-DA 40mm F2.8 XS lens. The latter bundle represents a US$100 discount over the cost of buying camera and lens separately, given that the lens alone has a list price of about US$250. The K-01 kits are offered in three versions: yellow with black and silver detailing, white with black detailing, or black with silver detailing. Each kit also includes a special neckstrap and packaging created by industrial designer Marc Newson.

Pentax K-01 Review

As predicted by the rumor mill at the start of 2011, Pentax didn't only plan the diminutive Pentax Q compact system camera, but also a second mirrorless camera with a larger sensor. And here it is: the Pentax K-01. Featuring a tweaked version of the sensor from the excellent Pentax K-5, the K-01 is also marked by a unique modern design. With a 16-megapixel sensor capable of shooting 1080p video, and body-based image stabilization, the Pentax K-01 is fairly up-to-date in the specs department. Because it uses an APS-C sensor and accepts standard K-mount lenses, the design is a lot thicker than most of the competition, as you can see in the top shot below.

Looking into its depths with the lens off, it is immediately obvious why the Pentax K-01 is so thick: the company had to maintain the same backfocus distance for compatibility with existing lenses. Essentially, it still has the same mirror box as an APS-C DSLR, even if there's no mirror inside it. (And the lack of a mirror emphasizes its cavernous nature.) Other mirrorless manufacturers have chosen to create a new lens mount and a whole new range of lenses to allow for a shorter backfocus distance. Pentax preferred to keep compatibility with their existing lens line while simply removing the mirror mechanism from the equation. As with the Q, Pentax has thought outside the box. One wonders if they may have missed the reason companies started producing mirrorless cameras: to make the overall camera and its lenses smaller, however.

Seeing the camera in person, as well as holding it, you don't get quite the same impression these photos give. For a mirrorless camera, the Pentax K-01 is large, heavy, and chunky. It's about as wide as the Olympus E-P3, but quite a bit thicker, at 2.3 inches compared to the E-P3's 1.4 inches. Dimensions are 4.8 x 3.1 x 2.3 inches (122 x 79 x 58mm) and weight is 19.8 ounces (1.2 pounds; 561g) with a battery and card, only 1.3 ounces lighter than the Pentax K-r. The prime 40mm kit lens that ships with it, shown above right, is quite slim and light, weighing just 1.8 ounces (51g).

The bold, wide curves and large elements don't do much to make the Pentax K-01 seem smaller, either. Going over the controls, the pop-up flash button is on the left, the large aluminum-alloy Mode dial is just right of the small flash housing. An aluminum-alloy control dial is behind that, flanked by green and red multi-function buttons that can be customized via the Button Customization menu, and the EV button. The red button is for movie recording by default, and the green button functions like the green-dot button on Pentax SLRs, recentering the exposure to what the meter would pick by default. The shutter button/power switch is near the front, inset from the grip area. The Pentax K-01's hot shoe accepts Pentax's current line of digital flashes, and the strap lugs are neatly integrated into the design, requiring no D-rings, for more quiet video recording.

There's plenty of room on the back for the 3-inch TFT LCD, sporting 921,000 dots and a 170-degree viewing angle. The Flash pop-up button on the top does double-duty as the Delete button in Playback mode. The other buttons and controls really need no explanation. The AF/AE-Lock button is well placed, as is the Playback button. Even the card write lamp is distinct and easy to understand. The yellow card door opens with a pull to the right.

Returning to the front, there's an AF-assist lamp beneath the Mode dial, an infrared remote port in the grip, and a lens release button is built into the lens bezel, which you can see right next to the SR (Shake Reduction) logo. On the lower right side of the lens is the MF/AF switch.

The yellow or black grip surfaces are soft and tacky, and the cameras are available in three color schemes at launch, including a white body with black grips, a black body with black grips, or a black body with yellow grips, as seen at right.

The pop-up flash springs up fairly high considering the size of its silo, and the Mode dial is very tall, making it easy to grip and turn. Regardless what you think of its looks, the Pentax K-01 is straightforward to use. Simplicity was clearly the goal, and I think the designer, Marc Newson, achieved that.

Sensor. We understand that the Pentax K-01's image sensor is closely related to that used in the company's flagship enthusiast SLR, the Pentax K-5. It's still an APS-C sized (23.7 x 15.7mm) RGB CMOS chip, approximately the same size as that used in all of the company's SLRs to date. The 16.28 megapixel effective pixel count stated for the K-01's imager is also identical to that of the K-5. Total resolution falls ever so slightly to 16.49 megapixels, from the 16.93 megapixels of the earlier camera's sensor.

Although the K-01's body is much thicker than its competitors, its sensor is no larger than those used by several compact system camera competitors including Sony's E-mount, Samsung's NX-mount, Fujifilm's X-mount, and several lens modules for the Ricoh GXR. It's quite a bit larger than the sensors used in Olympus and Panasonic's Micro Four Thirds mount, Nikon's 1-mount, and Pentax's own Q-mount, and significantly smaller than the sensors used by Leica's M-mount cameras.

The Pentax K-01 offers a native image resolution of 4,928 x 3,264 pixels with a 3:2 aspect ratio, identical to that of the K-5 SLR. Three lower-resolution options are also available, all of which are rather higher resolution than those offered by the K-5: 4,224 x 2,816, 3,456 x 2,304, and 2,688 x 1,792 pixels.

The K-01 also offers three alternative aspect ratios, all of which have a choice of four resolutions, and work by simply cropping the sensor data and discarding the unused pixels. The highest resolutions on offer in these modes are 4,352 x 3,264 in 4:3 aspect, 4,928 x 2,776 in 16:9 aspect, and 3,264 x 3,264 in 1:1 aspect.

Processor. Pentax has debuted a brand-new image processor in the K-01, which offers greater movie capture performance. Dubbed "PRIME M"--a contraction of Pentax Real IMage Engine, with the M presumably standing for Movie--the new processor replaces the rather long-in-the-tooth PRIME II model, which has featured in all Pentax interchangeable-lens cameras since the K-7, with the sole exception of the Pentax Q.

Where the company's flagship K-5 relies on less space-efficient Motion JPEG compression, and is limited to 25 frames-per-second capture at its maximum 1080p resolution, the K-01 now offers 1080p at 30 frames per second, with H.264 /MPEG-4 AVC compression. That's actually the same as was offered by the Pentax Q, although interestingly, the processor in that camera is unbranded in most markets*. The higher frame rate and new compression type aren't the only change in the K-01's movie capabilities, however. We'll come back to that in a moment...*As an aside, we're aware that Pentax UK brands the Q's processor as "Q Engine". We've yet to see that designation in press materials from other markets, though.

Sensitivity. Although the Pentax K-01 has a similar image sensor to that of the K-5, and its processor is more powerful, it has a slightly narrower sensitivity range than its SLR sibling. At the bottom end, the difference is only slight, with the Pentax K-01's base sensitivity being ISO 100 equivalent, where the K-5 can manage ISO 80 when ISO expansion is enabled. At the top end, there's a more significant variation between the two. Both cameras are ordinarily limited to ISO 12,800 equivalent, and the Pentax K-01 can manage a maximum of ISO 25,600 with expansion enabled. By contrast, the K-5 can reach as high as ISO 51,200 equivalent if ISO expansion is active.

Just like the company's other interchangeable-lens cameras, the Pentax K-01 also offers an Auto ISO function, whose range can be adjusted to encompass any available sensitivity.

Burst speed. Performance of the Pentax K-01 also trails the company's enthusiast SLR slightly in another area, although for JPEG shooting, it's still reasonably swift compared to many compact system cameras. Unfortunately, if you're a raw shooter, burst speed is decidedly subpar. Where the K-5 was rated by its manufacturer as capable of shooting at seven frames per second regardless of file type--we found a slightly more modest 6.5 fps in our in-house testing--the K-01's burst performance is rather lower. In JPEG mode, Pentax rates its APS-C system camera as capable of burst shooting at around six frames per second in Continuous Hi mode, pretty close to our measured speed of 5.93 frames per second. Unfortunately, for raw shooting this plummets to a lethargic 1.02 frames per second. Large / Fine JPEG buffer depths are around nine frames, while there is effectively no buffer at all for raw shooting. There's also a Continuous Lo mode offering three frames per second JPEG shooting.

The K-5 was already pretty quiet by SLR standards, but the K-01's burst shooting is even more so, thanks to the removal of the reflex mirror from the equation. It's certainly still audible, but you won't turn heads as you would with some competing models.

Lens mount. On its front panel, the Pentax K-01 features a stainless steel, KAF2 bayonet lens mount, which is also compatible with KAF3, KAF, and KA mount lenses. Both in-body and in-lens AF mechanisms are supported, but power zoom isn't possible with the K-01. Pentax K mount lenses can also be attached, as can 35mm screwmount and 645/67 medium format lenses using optional adapters, although there may be restrictions depending on the lens type used.

The decision to retain the same lens mount is a bold one, and makes the Pentax K-01 truly unique. As of this writing, every other compact system camera on the market has a new mount, and a relatively limited selection of optics from which photographers can choose. Most competitors have provided adapters to allow use of historic glass from their earlier SLR cameras, but these typically either have limitations in terms of focusing and exposure that may make their use less attractive. There are options such as Sony's Translucent Mirror-based adapter for NEX cameras that are fully-featured, but they're quite expensive and add significantly to the camera's bulk. The K-01, by contrast, can be used out-of-the-box with a vast selection of Pentax glass produced over a period of decades, as well as third-party glass for the Pentax K-mount.

Unfortunately, the decision is something of a double-edged sword: it also means that while the K-01 no longer has a mirror, it must still cater to lenses that were designed with one in mind. The flange focal distance of these lenses dictate the depth of the K-01's body, which is much the same as the company's smallest SLR cameras, if one excludes their hand grip. Had Pentax followed in its rivals' footsteps with a new mount for the K-01, it could still have provided backwards compatibility for its existing lenses via an adapter, and simultaneously offered a new line of lenses optimized for a smaller flange focal distance as an alternative to the older glass. This would have allowed a significant reduction in body depth, as well as some reduction in the size of dedicated lenses for the system. That's not the path Pentax chose, however, and so the K-01 has only a very modest advantage in size and weight over a full-fledged SLR camera, and no advantage in the size and weight of lenses at all.

Perhaps there is a reason other manufacturers haven't already gone down this road. We find ourselves struggling to see an advantage to the path Pentax has chosen for the K-01, beyond the initial savings in cost of designing another new mount and related optics.

Kit lens. Alongside the K-01, Pentax launched a new variant of its existing smc Pentax DA 40mm F2.8 Limited pancake lens. It's available to purchase separately, but it was clearly created with the K-01 in mind (and indeed, is available in a bundle with the camera.) Like the K-01 itself, the external styling of the new smc PENTAX-DA 40mm F2.8 XS lens is said to have been created by Australian industrial designer Marc Newson. Pentax bills this new optic as being "the world's thinnest interchangeable lens" as of this writing, and we believe them. It really is incredibly compact.

Here's the new 40mm compared to the older 40mm Limited lens.

Our sister site SLRgear.com has published a detailed review of the new 40mm XS lens, but given that it's the only kit lens option for the K-01, it bears looking at briefly here too. The diameter, optical formula and SP coating are unchanged from the existing lens, but the new lens is significantly smaller and lighter than the previous version. The depth of the lens--already pretty impressively short in the existing version--has been sliced almost in half, though. Where the earlier lens was 0.6 inches long, the new one is just 0.36 inches deep. Weight has also been cut almost in two, with the new lens weighing 1.8 ounces, where the older version weighs 3.2 ounces.

The reduction in size and weight were achieved by trimming off most of the lens barrel beyond the front element of the lens, making the new version arguably rather more prone to flare--and there's no longer any support for a lens hood to combat this. That change was most likely made because the filter threads are no longer placed near the edges of the lens' circumference. Instead, they're located nearer to the front lens element. This means that the new lens uses much smaller 27mm filters, rather than the 49mm filters of the earlier version, and would likely cause vignetting if you use deep or stacked filters. Of course, a simple step-up ring to a larger filter size would help here.

There are a couple of other notable differences. The markings for focus distance have been removed, so if you find yourself relying on these when focusing manually, you'll likely prefer to use the older version of the lens. Also, there's a new rubber lens cap that--while much faster in use than the screw-on metal cap of the original design--is a bit fiddly to seat properly, and quite easily knocked off by mistake even when properly seated.

Although the optical formula is unchanged, our testing for the SLRgear lens review found the new version to be significantly less sharp than the existing Limited version, and with noticeably better control of chromatic aberration. The screw-drive autofocus is however slightly quieter, although focus speed doesn't seem to differ on the K-01 body, even though there's much less mass to be shifted during focus operation.

The main difference, though, is the price: compared to the original Limited version, the XS variant costs literally half as much. And that, at the end of the day, is the reason to go for this lens rather than the original version. With the exception of size, the other differences are relatively slight, and largely favor the more expensive version. Given that the K-01 has a much larger body than is the norm for a compact system camera, size is unlikely to be of huge significance to anyone buying this lens, especially given that the Limited version itself is already one of the smaller pancakes around. That difference in price could put another lens in your camera bag, though.

Autofocus. Like almost all mirrorless cameras, the Pentax K-01 relies on a contrast detection autofocus system, which operates based on data provided by the image sensor. The same technique has been the default for focusing in live view mode on Pentax cameras since the K-7, and indeed, it's the only option on the Pentax Q. Phase detection autofocusing isn't possible with the K-01.

Although there aren't physical focus points per se, the Pentax K-01's contrast detection operates as if there was an 81-point array, a significant step up from the 25-point AF of the Pentax Q. (This differs from live view on the company's SLRs, however, which didn't offer predefined focus points, but rather allowed the focus point to be positioned almost anywhere within the image frame.)

The K-01's autofocus system is said to have a working range of EV 1 to 18, at ISO 100 equivalent. By way of comparison, the dedicated SAFOX IX+ phase detection autofocus sensor in the K-5 has a working range of EV -1 to 18 at ISO 100, making it theoretically able to focus in lower lighting conditions than could the K-01. Of course, phase detection AF systems have their own issues of focus accuracy, where contrast detect systems don't typically suffer issues with front- or backfocusing.

Autofocus modes on offer in the Pentax K-01 include single, face detection, and tracking. The face detection system is capable of identifying up to 16 faces within the image frame simultaneously. Focus points can be selected automatically or manually, or the camera fixed to use only the centermost point. To help out with autofocusing in low light conditions, the K-01 includes an LED autofocus assist lamp. Autofocus accuracy can be confirmed via a 2x, 4x, or 6x AF autozoom function.

Focus Peaking. Of course, it's also possible to focus manually, if you prefer. Here, there's a significant addition to the K-01's repertoire when compared to Pentax's previous cameras, and one that makes manual focusing without an optical viewfinder a much easier proposition. The new Focus Peaking function is something we've seen from other manufacturers previously, for example in Sony's NEX-series compact system cameras. This highlights the areas of highest microcontrast within the image frame, adding a lighter halo similar to an overzealous unsharp mask. As you rack focus back and forth, this peaking indication lets you see where the in-focus areas of your image lie. The implementation differs from other manufacturers, who typically highlight with a specific color. Pentax's method makes it easy to see which image areas are closest to being correctly focused in most conditions, but can be a bit subtle when trying to manually focus on a dark subject, appearing as a very faint shimmer.

Shake Reduction. Just like all of the company's interchangeable-lens cameras with the exception of the medium format 645D, the Pentax K-01 includes in-body image stabilization. The K-01's image sensor assembly is mounted on a ball-bearing supported moveable platter, allowing for sensor-shift image stabilization, or Shake Reduction, in Pentax parlance. The system is compatible with all Pentax interchangeable lenses produced to date. Pentax claims that four stops of correction can be achieved by the K-01's sensor shift system, the same level as in the company's recent SLR models. We believe Pentax's Shake Reduction mechanism is limited solely to horizontal and vertical shake, as are most such systems. (Only a few, such as those in the Pentax K-5 and K-7 SLRs, can correct for rotation around the axis of the lens barrel.)

One of the main disadvantages of sensor shift stabilization--as compared to lens-based stabilization--is the fact that there's no way to offer a stabilized viewfinder view. With no optical viewfinder in its design, the Pentax K-01 neatly sidesteps that issue. Since the view on the camera's LCD monitor comes from the image sensor, the live view feed can be stabilized, letting you preview the framing you'll get when you trip the shutter.

Dust removal. The Pentax K-01 has a dual-pronged approach to dust reduction. The K-01's low-pass filter is overlaid with Pentax's Super Protect (SP) coating, which aims to prevent dust particles from adhering in the first place. Should any dust particles adhere, the K-01 uses motion of its sensor shift mechanism in an attempt to shake them free. Much the same system is used by most Pentax SLRs, as well as in some competitors' cameras, but we've typically found that cameras using dedicated piezoelectric elements to provide the vibration are more effective at dust removal, perhaps due to the higher frequencies that are possible.

(No) Viewfinder. Like all mirrorless cameras, the Pentax K-01 lacks an optical viewfinder. Unlike some, it also lacks any provision for an electronic viewfinder--either built-in, or as an external accessory. It's a decision that has allowed the company to skim a little bit off the height of the camera body compared to its smallest SLR models, but it's also one that means you'll be doing all of your interaction through the LCD panel.

LCD. The K-01's LCD is unchanged from that featured in the K-7, K-r, and K-5 SLRs. It has a 3.0-inch diagonal, and offers 921,000 dots of resolution. This equates to an array of roughly 640 x 480 pixels, with each pixel comprising separate red, green, and blue dots. The display offers wide 170 degree horizontal and vertical viewing angles, and has both a brightness and color adjustment.

Metering. For much the same reasons that it lacks a dedicated autofocus sensor--the lack of anywhere in the optical path to place one--there's also no dedicated metering sensor in the Pentax K-01. Like any compact system camera, exposures are metered using the image sensor itself.

Pentax's recent SLR cameras have all featured either 16-segment or 77-segment metering sensors, and the Pentax Q followed suit with a 16-segment metering system, albeit derived from the image sensor. The K-01 bucks that trend with a much finer-grained 1,024 segment metering system, however. The K-01's metering system has a working range of EV -1 to 21 at ISO 100 with a 50mm f/1.4 lens. By way of comparison, the dedicated 77-segment metering chip in the K-5 has a working range of EV 0 to 22 under the same conditions.

As well as the 1,024 area multi-segment metering mode, the K-01 also offers both center-weighted and spot metering. A dedicated AF/AE-L button lets you lock the metered exposure, useful for spot metering on a particular subject before composing your final image.

Exposure compensation is available within a range of +/-3.0 EV, in either 1/3 or 1/2 EV steps. It's also possible to bracket exposures across three frames, within the same range of +/-3.0 EV, but with a fixed 1/2 EV step size. Bracketed exposures are captured with a single press of the shutter button, and there's no preview between frames. That can make it challenging to keep framing exactly the same between shots without using a tripod; indeed it's near-impossible to do if you also have a digital filter active as there's around a second between shots.

Exposure Modes. Although it shares much of its DNA with the enthusiast-oriented K-5 SLR, a glance at the Pentax K-01's Mode dial reveals a rather different target customer. Gone are the more obscure exposure modes from the K-5, like Sensitivity Priority or Shutter-and-Aperture Priority. There are also no User or X-sync modes. In their place are two friendlier offerings which an amateur photographer might seek out: Auto Picture, and Scene. There are no less than 19 scene modes on offer, including Portrait, Landscape, Macro, Moving Object, Night Scene Portrait, Sunset, Blue Sky, Forest, Night Scene, Night Scene HDR, Night Snap, Food, Pet, Kids, Surf & Snow, Backlight Silhouette, Candlelight, Stage Lighting, and Museum. If you find that overwhelming, the Auto Picture mode can automatically select from a subset of these: Standard, Portrait, Landscape, Macro, Moving Object, Night
Scene Portrait, Night Scene, Blue Sky, or Forest.

Enthusiasts will spend most of their time in the Program, Aperture- and Shutter Priority, Manual, and Bulb modes, however, all of which also merit their own positions on the Mode dial. There's also a separate Movie mode, even though the K-01 now has a dedicated Movie button on its top deck. (Videos recorded from modes other than the Movie mode use Program autoexposure.) Two final Mode dial offerings are HDR, and Flash Off.

HDR. Pentax has included an updated version of its HDR mode in the K-01. As in earlier models, this allows capture of images with greater dynamic range than the sensor is capable of detecting, by taking multiple images with varied exposure, and then combining them to produce a single shot with increased dynamic range. Since it involves multiple exposures, it's only useful for relatively static subjects, although as in the Pentax K-5, the function is capable of performing some microalignment, and hence is able to be used handheld. (Some cameras don't attempt to align the source images, making HDR photography impossible unless the camera is tripod-mounted.)

The K-01's HDR mode still saves images in JPEG format only, but now offers three different step sizes between exposures: either one, two, or three EV. There are also three choices for the look of the effect, which control whether you get a flatter, more natural-looking image, or one with a crunchy, high-contrast feel. Additionally, the K-01 can automatically choose the look based on the scene being photographed. HDR images can also be captured from other exposure modes via a menu option, but this doesn't provide control over exposure steps.

Drive Modes. In addition to the previously described 6 frames-per-second Continuous Hi and three fps Continuous Lo modes, the Pentax K-01 offers a variety of other drive mode options. These include a 2 and 12-second self-timer, as well as an immediate or three second delayed infrared remote release. The remote modes require an optional remote control unit, and the K-01 is compatible with the same two IR remotes as other recent Pentax cameras: the tiny Remote Control F, or the weather-sealed Remote Control WP. The former has only one button with which to trip the shutter. The latter has three buttons, one of which trips the shutter, and one of which can be used to perform an AF cycle without releasing the shutter.

Shutter. The Pentax K-01 has an electronically controlled, focal plane shutter unit, capable of a maximum 1/4,000 second shutter speed, just half the 1/8,000 limit of the K-5 SLR. Minimum shutter speed is 30 seconds, and as noted previously, a Bulb position is also available.

White balance. The K-01 offers a fairly wide range of white balance settings. As well as Automatic and Manual modes, there are no less than ten white balance presets (Daylight, Shade, Cloudy, Daylight Color Fluorescent, Daylight White Fluorescent, Cool White Fluorescent, Warm White Fluorescent, Tungsten, Flash, and Color Temperature Enhancement). This last option was first introduced on the Pentax K-7, and has since been mimicked by the company's competitors. It's used to retain and enhance the lighting tone - for example, to enhance a sunset.

All white balance modes in the K-01 offer a fine adjustment function that lets you tweak the white balance, if the standard result isn't quite to your liking. There are also two Custom functions related to white balance. One lets you override the configured setting with either Auto or Flash white balance when the flash is active, and the other determines whether auto white balance in Tungsten light should retain some warmth or not.

Flash. As well as a P-TTL-compatible hot shoe for external flash strobes, the Pentax K-01 includes a built-in popup flash. With a guide number of 12 meters at ISO 100, the K-01's onboard flash is the same as that of the K-r SLR, and just slightly weaker than those of the K-5 and K-7, which have a guide number of 13. The K-01's popup flash offers 28mm coverage, and includes red-eye reduction capability.

X-sync is at 1/180 second, just like the company's SLRs, and the K-01 supports High Speed Sync with Pentax's external strobes. It also offers -2 to +1EV of flash exposure compensation, and can provide both first- and second-curtain flash. The internal strobe does not support Pentax's wireless flash system.

Movie mode. When Pentax debuted the K-7 SLR back in 2009, it was a little ahead of the game, being the first to offer aperture control for video capture. Since then, the company's video functionality hasn't developed as quickly as the rest of the market, and recent models have rather lagged the competition when it came to video capture capabilities. The company has clearly put quite a bit of work into resolving that for the K-01, and its movie-mode functionality has received quite an overhaul.

Like the tiny Pentax Q, the K-01 now records videos with more modern H.264/MPEG-4 AVC compression, which is rather more space-efficient than the archaic Motion JPEG compression used in its SLR cameras. (Of course, it also takes a more powerful computer to edit, and some might argue that Motion JPEG has the potential for higher image quality, but with the Pentax K-5 requiring as much as 600MB of storage per minute of video captured, it was clear that a more modern compression format was needed.)

The K-01 also bests Pentax's enthusiast flagship in terms of video frame rate, being able to capture Full HD (1,080p; 1,920 x 1,080 pixel) video at a rate of 30 frames per second, where the K-5 was limited to 25 frames per second. Better still, it's possible to opt for frame rates of 25 or 24 frames per second, if that better suits your target for the recorded video. In addition, at 720p (1,280 x 720 pixel) resolution, it's now possible to record at 50 or 60 frames per second. There's still a VGA (640 x 480 pixel) mode, as well, if you prefer to capture in standard-def, and this offers the same frame rate options as the Full HD mode.

That's not all, though. The K-01 now offers a choice of either program, aperture-priority or manual capture, where--with the exception of the Pentax Q, which offered a choice of Program or Manual exposure--previous Pentax models have been limited to only program or aperture-priority. (Shutter-priority capture is still not available though.) It's also now possible to change shutter speed, aperture, and ISO sensitivity during movie capture, but only by using the E-dial, which has such a firm detent that it leaves a fairly loud noise on the audio portion of your movie with each click, if recording with the internal mics.) You can also choose either a manual or automatic control of ISO sensitivity in Manual exposure mode, providing something akin to the shutter-and-aperture priority (TAv) mode of Pentax SLRs. Unlike in still image shooting, you can't adjust the range of sensitivities available to the Auto ISO function, however.

The K-01 also inherits the Pentax Q's ability to create time-lapse movies in-camera, great for making a video of a flower opening, tides ebbing and flowing, or weather patterns in a cloud-scattered sky.

Movie audio has also been revisited, with a built-in stereo microphone in place of the monaural mics of past models, plus a stereo mic jack for external mics. There's also both a wind noise suppression filter, and a manual audio gain control. The latter provides five-step control over internal mic levels, and ten-step control over levels of external mics, and also allows either mic type to be disabled if preferred.

Pentax has also rethought its movie-mode interface, and now offers not only a separate Movie position on the Mode dial, but also a dedicated Movie record button. Movie capture is now possible from other modes, as well, although the movie crop is not indicated until capture starts. Still, that change along is a very worthwhile improvement, as having to change modes makes it less likely you'll be fast enough to grab a spontaneous clip, when an unanticipated opportunity presents itself.

GPS. Although the K-01 doesn't offer built-in GPS functionality, it is compatible with Pentax's hot-shoe mounted O-GPS1 accessory. This offers the ability to geotag your images with information about the capture location, including capture direction from an electronic compass. It can also be used to automatically correct the camera's internal clock. Sadly, it doesn't support Pentax's clever Astrotracer function, which allows some models to freeze star motion during long exposures, preventing star trails from forming. Nor does it support the simple navigation function.

Power. The Pentax K-01 accepts the exact same D-LI90 lithium-ion battery pack as the Pentax K-5 and K-7. The D-LI90 is a 7.2V pack rated at 1,860 mAh / 14Wh. Showing how much power full time live view requires, battery life is 500 shots to CIPA testing standards (including 50% flash usage), down from 740 shots with the Pentax K-5 using the same battery. Pentax also rates the K-01 as good for 320 minutes of playback on a charge, down from 440 minutes in the K-5. For studio shooting, or while offloading data via USB, the K-01 can also draw power from Pentax's optional K-AC1202 AC adapter kit. This interfaces with the camera using a dummy battery, which attaches to the AC adapter via a cable. A small rubber flap in the battery door allows it to be closed with the dummy battery inserted.

Storage. The Pentax K-01 stores images and movies on Secure Digital cards. Not only does it support the higher-capacity SDHC and SDXC cards, but it now also supports higher-speed UHS-I Class 1 cards. Images can be saved in either JPEG or raw formats, although the K-01's raw files are 12-bit, rather than the 14-bit raws of the company's enthusiast SLRs. As in the Pentax Q, the company has dropped its proprietary .PEF raw format, in favor of Adobe's more open .DNG raw files. (Earlier Pentax models allowed the user to select their choice of format.)

Creative. The Pentax K-01 offers the same selection of Custom Image modes found in the earlier Pentax Q compact system camera. These include Bright, Natural, Portrait, Landscape, Vibrant, Radiant, Muted, Bleach Bypass, Reversal Film, Monochrome, and Cross Process modes. All except Cross Process can be tweaked to the user's tastes, while Cross Process effects are random, but if you get a random effect you particularly like, you can save it for later recall.

The K-01 also offers a variety of pre- and post-capture filter effects. Before capture, you can select from Extract Color, Toy Camera, Retro, High Contrast, Shading, Invert Color, and Color filters. After exposure, there's a much greater range of effects on offer, including Monochrome, Extract Color, Toy Camera, Retro, High
Contrast, Shading, Invert Color, Color, Tone Expansion, Sketch Filter,
Watercolor, Pastel, Posterization, Miniature, Soft, Starburst, Fisheye, Slim,
and Base Parameter Adjustment. Post-capture effects can be stacked, so that for example you could have a Watercolor filter combined with the Extract Color filter, yielding a largely monochromatic, painted effect with one color range retained.

The K-01 also retains the multiple exposure and interval timer effects seen in the Pentax K-5 SLR. The latter allows you to capture as many as 999 shots, at intervals of one second to one day, while the former provides the ability to overlay anywhere from two to nine exposures into a single final image.

Copyright. Another handy feature retained from earlier models allows you to specify a copyright holder for storage in the EXIF header of photographs. This is entered via the camera's menu system, unlike some competing cameras, which require it to be set via an attached computer.

Software. Like the Pentax Q before it, the K-01 now ships with Silkypix Developer Studio 3.0 software, providing for image editing and raw file development on both the Windows and Macintosh platforms.

Pentax K-01 Comparisons

Pentax K-01 vs Pentax K-r

Up against the K-r with the older 40mm pancake lens, it's clear that the K-01 isn't that much smaller. Height is the one obvious benefit of removing the pentamirror.

But thickness isn't that different. In fact, it seems like they could have included more of a grip and they wouldn't have exceeded the thickness of the camera and lens. Note that the back of the K-01 is flat, while the K-r's viewfinder tilts the back of the camera up in this shot.

Controls are essentially identical to the K-r's, so there's not actually much improvement in terms of simplicity.

Pentax K-01 versus Nikon V1

From the front, the Pentax K-01 and Nikon V1 don't seem that different, except for the size of the lens. As it is, I think the Nikon V1 is a little large for the compact system camera market, but not compared to the K-01.

It's when you look at them from the top that there's a noticeable difference in size and thickness, and the size of the lens. The V1 also has a protruding electronic viewfinder that tilts the camera up from the surface of the light table.

From the back again, there seems to be little difference in size, until you consider that the Nikon V1 manages this size while including an electronic viewfinder.

Pentax K-01 versus Olympus E-PM1 Pen Mini

The Pen Mini is the direction mirrorless cameras are headed, but the K-01 still uses existing lenses, which has its own benefits.

Still, when you add the standard Pentax kit lens, the difference is noticeable.

The Pen Mini also uses a 16:9 display instead of the K-01's 4:3 display. Neither is better than the other, just different. Both have fairly simple controls, but the K-01 has the benefit of a physical Mode dial, while the Pen Mini relies on an onscreen mode selection menu.

Pentax K-01 Field Test

As you'd expect given that its sensor is similar to that in the much-praised K-5 DSLR, the Pentax K-01's images show lots of detail. In this shot, almost every brick in the 1930s apartment building is distinguishable.

I'd be remiss if I didn't start my thoughts on the Pentax K-01 with a discussion of its Mark Newson-designed body. Mr. Newson is apparently a rather famous industrial designer, and Pentax has gone to great lengths to emphasise his involvement, after all. The unusual styling is, of course, the first thing you notice when you take the camera out of the box. Newson's signature is right next to the compartment door when you flip the K-01 over to insert the battery. On switching the camera on, you're reminded once more with the Newson-autographed boot screen. The company's marketing materials also highlight his connection to the project.

Frankly, I'm the kind of photographer who values function over form. A lot of cameras cross my desk, and while I favor the styling of some more than others--the Pentax K-01 falling squarely in the latter camp--I am most certainly not going to make the choice of which camera will accompany for a day's shooting based on its looks. Even if I mightn't be the target customer for the K-01's chunky design ethic, I'd gravitate towards it naturally were the shooting experience great.

The problem is that to me, the design places the cart before the horse. To achieve its blocky aesthetic, function has taken a very distant back seat. The Pentax K-01 is not a camera that feels comfortable in my hands for any length of time. That's in part due to its greater mass than is typical for a mirrorless camera. More than that, though, it's because of its sharp angles, its extremely shallow hand grip compared to the body thickness, and the fact that even with only the incredibly light 40mm XS lens mounted, it doesn't feel well balanced. Nor are some of the controls well placed. Pentax's ubiquitous (and oh-so-useful) Green button is hard to reach without adjusting my grip, and that's even with my larger-than-average hands. It's also far too close to the rear of the camera, as are the Exposure Compensation and Video buttons. I found the latter near-impossible to press without jostling the camera at the start and end of every video clip, unless shooting two-handed.

Perhaps even more annoying, though, was the rubber flap over the card compartment and most of the connectors. (A second, smaller flash card door beneath is required to ensure the camera stops writing before you pull the card out.) It's too easily opened by mistake, easily catching on a shirt button if you have the camera around your neck, for example. Worse, it's far, far too fiddly to close when you're done. Even using index fingers and thumbs of both hands to press it back in place, you generally have to go back and adjust the flap at a couple of points to get it to sit true. Pentax doesn't officially claim Eye-Fi card support for the K-01, but if I ever saw a design that was an argument for sticking one of these WiFi-capable flash cards in the body and then gluing the compartment shut, this would be the one.

The form factor of the Pentax K-01 doesn't entirely make sense to me, either. While it does offer the unique ability to mount a huge selection of historic Pentax glass without an adapter or feature limitations, it keeps most of the bulk of an SLR camera in the process. That negates the main advantage of a mirrorless camera, which is the ability to reduce size and weight of both camera and lenses. Other than the addition of a small viewfinder hump, I see no reason why Pentax couldn't offer an SLR camera of almost the exact same size as the K-01, and indeed they've actually come close in the past. And that SLR could be made to offer literally every feature of the K-01, simply by lifting the mirror.

In removing that mirror, though, you throw away some really useful features. For a modest increase in size, the optical viewfinder can provide you with a great view of the scene you're framing, without using any battery power at all. By contrast, the K-01 is hoovering up power the whole time you're even considering shooting an image. Switch it off, and you've no way to consider framing beyond using your imagination. Like most polarized LCDs, the K-01's display also turns dark the minute you try and frame a portrait shot, if you're wearing polarized sunglasses. (I lost count of the number of times I went to take a portrait shot on a sunny day, and double-checked that the camera was switched on, before the "Eureka" moment. And of course, you lose the phase detection autofocus sensor. That means you must rely on slower contrast detection AF.

The Pentax K-01's contrast detection autofocus isn't just slower than phase detection, either. I also found it to be significantly less reliable, both with the 40mm XS kit lens that shipped with the camera, and with my own stock of lenses, including a 21mm f/3.2 Limited pancake, an 18-55mm kit zoom, and a 50-200mm telephoto zoom. On far too many shots, the K-01 indicated a focus lock, took the picture, but actually missed focus entirely. Sometimes it was by a significant margin, and I could reshoot immediately. Other shots looked fine on the camera's LCD, but were visibly out of focus once I got them onto my PC back home. The 50-200mm lens also had an annoying tendency to rack through the entire focus range before even attempting to focus for a shot, adding a second or two of waiting around, and causing me to miss spontaneous exposures. All of these lenses work just fine on my own K-5 and K-7 camera bodies, both using phase detection and contrast detection autofocus modes.

Default

Extract Color

Toy Camera

Retro

High Contrast

Shading

Invert Color

Color

Digital filters can be a lot of fun if you're the type who prefers to avoid post-processing on your computer. The Pentax K-01 offers plenty, and most are adjustable. Above is just the pre-capture selection; there are lots more applicable only after capture.

The Pentax K-01's unsatisfying autofocus actually made me want to use manual focus more often, something that was made significantly more enjoyable by the new focus peaking function. In fact, I'd very much like to see the same function on my K-5 body. I'm definitely going to miss having a peaking function on hand...

When I'm shooting for myself, I'm exclusively a raw shooter. I typically shoot raw+JPEG when I'm shooting galleries for our camera reviews, so you can see both raw and out-of-camera JPEG shots as your own preferences dictate. Unfortunately, the K-01's raw performance is disappointing. There is effectively no buffer at all: the K-01 will shoot raws at the same speed until the cows come home (or your flash card is filled), but it will do so at barely one frame per second. If you're a JPEG shooter, things aren't so dire. The JPEG burst depth is admittedly rather limited, but burst performance doesn't trail too far behind Pentax's best SLRs.

The Pentax K-01 isn't well-suited to sports shooting, thanks to slow burst shooting in raw mode, and slow contrast detection autofocus. Switch to JPEG mode and you can get nice results so long as subject distance isn't changing too fast, though.

One situation in which I found even JPEG shooting to be less than fun, however, was capturing bracketed exposures with a digital filter enabled. With bracketing active, the K-01 captures all three frames with a single press of the shutter button, and doesn't return to live view between frames. That's fine for both raw and JPEG shooting--the one situation in which the K-01 does seem to be able to hold more than one raw image in its buffer--but if you enable a digital filter, the processing is done between frames. The filters typically take around a second to apply, so by the time the third frame is captured, you've been trying to hold the camera steady for over two seconds without any way to see your framing. If you're using filters, you're better off bracketing your shots manually, rather than using the exposure bracketing function.

JPEG burst performance also wasn't great if using focus tracking, thanks to the rather sedate contrast detection autofocus, and the time it takes to tweak focus between frames. For subjects moving towards or away from me at any significant speed, burst shooting slowed to a crawl, and the Pentax K-01 struggled to achieve a focus lock even more than usual. This is not a camera for sports shooters, sorry to say. That's not to say you can't get sports shots with it: on the contrary, as my jet ski shot above demonstrates. You'll just need to rely either on focusing manually, prefocusing, or on shooting only subjects whose motion is predominantly lateral across your field of view. And of course, you'll need to disable raw mode.

Low-light shooting is one area in which the K-01 shines. This handheld shot was taken fifteen minutes after sunset, on a dimly lit street.

It may seem that I'm being a bit unkind to the K-01, but I must admit, I can forgive many of its quirks for its imager. It's closely-related to the much-praised sensor in the Pentax K-5, and that is definitely a good thing. While the tweaks that have been made--I believe to achieve a higher live view refresh rate and more capable video capture--do seem to have brought about a slight reduction in image quality when compared to the K-5, the Pentax K-01 is still capable of some mighty pleasing images. And I do see the advantage of shooting with my existing glass, rather than needing to buy (and learn the foibles of) an entirely new stock of lenses.

In particular, the Pentax K-01 shines for low, available light shooting, something I've also greatly enjoyed with my K-5. Even dim street lighting is plenty to get handheld shots you can be pleased with, without resorting to ugly on-camera flash or bulky, ungainly external strobes. The profusion of in-camera filter effects are also a lot of fun, as are the more unusual functions like multiple exposure and interval shooting, in-camera HDR, and the like. Perhaps having been trained by the HDR function that hides in the menu of my K-5, I did tend to forget the dedicated HDR mode on the Mode dial. You can't control the exposure step size from the menu's HDR mode, though, something I'd like to see change. While the dedicated HDR mode allows the step size to be changed, it simultaneously prevents you dialing in your chosen aperture for the HDR series, preventing any depth-of-field effects.

The changes that Pentax has made to the video mode of the K-01 are also welcome. I'm the first to admit that I'm not much of a videographer, mind you. I simply don't have the mindset to plan and capture a story across multiple shots, then stitch everything together in an editor when I get back home. Instead, I tend to shoot single clips documenting a specific moment I'm interested in, and let them stand alone. Even I could appreciate the ability to manually control all three main exposure variables, though. I also found manual focus during video capture with the new 40mm XS lens to be a joy, providing for some fun effects. I'd wager that a talented videographer could do quite a lot with this camera, and if I owned one the video functionality would probably get quite a bit more use than does that of my K-5.

Standard exposure

Auto HDR

HDR 1

HDR 2

HDR 3

The K-01's HDR mode is usable handheld if your subject is relatively static. These shots at 300mm-equivalent were micro-aligned in-camera. I tended to forget there was an HDR mode on the Mode dial, though, which would've allowed me to adjust the exposure step size. I'd have liked to see this option available regardless of exposure mode.

Note that the last shot is more saturated because it used Color Temperature Enhancement (CTE) white balance. I shot a series with each, but didn't lock focus from the first shot, and at least one shot in each series missed the focus slightly. By the time I realized, the sunset was gone...

The shame is that with the same processor and imager, Pentax could have offered these same advantages in an SLR body not much larger than that of the K-01, without the sacrifices that are made, essentially, just to remove the viewfinder. Such an SLR wouldn't be much bigger than the K-01, and I doubt it would be that much more expensive either. With the mirror locked up, the SLR would be able to provide the same feature set as the K-01, and with it dropped it would retain the much more usable phase detection AF and a proper viewfinder.

While I think it was mighty bold of Pentax to offer two completely separate mirrorless camera systems, I feel they've missed the mark with the K-01. Unless you absolutely cannot stand shooting with an optical viewfinder, or you need the smallest possible body with a K-mount on the front, I would recommend looking at one of the company's other SLR models instead. The flagship Pentax K-5 is mighty tempting at its current street price, and the early signs are that the upcoming Pentax K-30 will be offering a a lot of camera for the price, as well.

Pentax K-01 Image Quality

Most CSCs and SLRs will produce very good base ISO shots, so we like to push them and see what they can do at ISO 1,600. Recent advances in sensor technology have made ISO 1,600 look a lot more like ISO 100, but there are still cameras whose quality starts to fall apart at this setting. I also choose 1,600 because I like to be able to shoot at least at this level when indoors and at night.

NOTE: These images are best quality JPEGs straight out of the camera, at default settings including noise reduction. All cameras in this comparison were shot with our very sharp reference lenses.

Pentax K-01 versus Pentax K-5 at ISO 1,600

Pentax K-01 at ISO 1,600

Pentax K-5 at ISO 1,600

Noise suppression seems more active with in the K-01, with artificially smooth areas in the shadows, and our tough red leaf swatch is noticeably more obliterated than it is in the K-5. More sharpening and processing is also evident in the mosaic image and even the Mas Portel bottle.

Pentax K-01 versus Olympus E-P3 at ISO 1,600

Pentax K-01 at ISO 1,600

Olympus E-P3 at ISO 1,600

The Olympus E-P3 leaves a little more chroma noise in the shadows, but itself does a little too much processing in the mosaic swatch; it also has less information to work with, considering its 12-megapixel resolution. Still, the E-P3 retains a sense of the leaves in the red leaf swatch.

Pentax K-01 versus Panasonic G3 at ISO 1,600

Pentax K-01 at ISO 1,600

Panasonic G3 at ISO 1,600

With both sensors about 16 megapixels, the Pentax K-01 does fairly well overall, with better color and better contrast, but more noise suppression than the Panasonic G3. For its part the G3's sensor is quite a bit smaller, but it still retains more detail in the red leaf swatch.

Pentax K-01 versus Samsung NX200 at ISO 1,600

Pentax K-01 at ISO 1,600

Samsung NX200 at ISO 1,600

Despite larger image elements thanks to its 20-megapixel sensor, the Samsung NX200's image is about as processed as the K-01, especially the Mosaic image. Though the NX200 gets credit for retaining more of the appearance of the red leaf swatch.

Pentax K-01 versus Sony NEX-5N at ISO 1,600

Pentax K-01 at ISO 1,600

Sony NEX-5N at ISO 1,600

Sony's approach also includes heavy noise suppression, but they do a better job with detail, including threads in the pink swatch and detail in the red leaf swatch. Note the sharpening halos in the NEX-5N's rendering of the Mas Portel label, though.

Today's ISO 3,200 is yesterday's ISO 1,600 (well, almost), so below are the same crops at ISO 3,200.

Pentax K-01 versus Pentax K-5 at ISO 3,200

Pentax K-01 at ISO 3,200

Pentax K-5 at ISO 3,200

Though its sensor is said to be closely related to that in the K-5, there's still noticeable difference to the K-01's approach to noise suppression. Overall, we prefer the K-5's more even-handed approach.

Pentax K-01 versus Olympus E-P3 at ISO 3,200

Pentax K-01 at ISO 3,200

Olympus E-P3 at ISO 3,200

The Olympus E-P3 starts to lose color saturation at ISO 3,200, and chroma noise is a little louder in the shadows. The E-P3 also sharpens a bit more than the K-01. It's almost a draw, but I'd call slightly in favor of the K-01 given the stronger detail.

Pentax K-01 versus Panasonic G3 at ISO 3,200

Pentax K-01 at ISO 3,200

Panasonic G3 at ISO 3,200

A slightly different aspect ratio makes the G3's image elements a little larger, giving it a bit of an advantage in this comparison. However, it's darker rendering doesn't help matters much.

Pentax K-01 versus Samsung NX200 at ISO 3,200

Pentax K-01 at ISO 3,200

Samsung NX200 at ISO 3,200

Samsung's NX200 has a lot more trouble overcoming chroma noise at ISO 3,200. As a result, we prefer the K-01's rendering.

Pentax K-01 versus Sony NEX-5N at ISO 3,200

Pentax K-01 at ISO 3,200

Sony NEX-5N at ISO 3,200

It's pretty clear that the Sony NEX-5N looks quite a bit better than the K-01.

Detail comparison. High-contrast details are often sharper as ISO rises, so they're worth a look as well. The K-01's contrast suffers a bit as ISO rises, especially noticeable when compared to the K-5. Sharpening halos are about as pronounced as most of the other cameras in the lineup. The K-01 maintains the lines inside the letters fairly well compared to the E-P3 and NX200 at ISO 6,400. The red letter, however, appear softer and darker than most.

Pentax K-01 Print Quality

Good color and detail at ISO 100, easily making 20 x 30-inch prints; ISO 3,200 images make a good 13 x 19-inch print; ISO 25,600 shots are good for a 5x7.

Autofocus is slow and proved surprisingly unreliable, both in the lab and the real world

Poor low-light focusing beyond range of AF assist

Sluggish power-on and mode switching

Very slow burst mode with raw files (1 fps)

Subtle noise reduction in high ISO raw files that can't be turned off

No live preview between frames for bracketed exposures

Prime kit lens doesn't offer good macro performance

Press-fit lens cap on kit lens is easily knocked off, likely to be lost

Default saturation and contrast quite high (as is typical for Pentax)

Contrast setting impacts saturation

No wireless flash support

No support for Astrotracer function on optional GPS receiver

With the Pentax K-01, the company treads new ground. It's a bold move, making Pentax the only manufacturer to offer two distinct mirrorless product lines, and the only one to offer a way to use existing SLR glass on mirrorless without an adapter. We can't help thinking that there's a reason other manufacturers haven't been down this road, however. In retaining support for existing K-mount lenses, Pentax has presented a camera that still has most of the size of an SLR, but loses its most important advantages over mirrorless cameras: the fast phase-detect autofocus, and the optical viewfinder. In their place, the Pentax K-01 has slow and too-often unreliable contrast detection autofocus, and offers no viewfinder at all--not even an external accessory. The lack of a viewfinder is a shame, but to some extent made up for by above-average battery life thanks to a full-sized battery the same as in Pentax's SLRs. The autofocus issues, though, are very disappointing indeed, and lead to entirely too many missed shots.

That's a great shame, because the best feature of the Pentax K-01 has to be its image quality. The sensor used is closely-related to that much-lauded in the company's flagship K-5 SLR, and it shows. While the K-01 doesn't quite match that camera for image quality, it comes fairly close. Images shot with the K-01 are pleasing indeed, when they're in focus, and the low-light / high ISO performance is excellent. Add in a great mix of creative features, and an updated movie mode that now allows fully manual exposure control, and you have a camera that could've provided a lot of fun, along with some great photographic results. Of course, you can focus manually, and the new focus peaking function makes light work of this.

As we conclude this review, we're left wondering what niche, exactly, that the Pentax K-01 is supposed to fill. Its chunky body seems to couple the main disadvantages of a mirrorless camera with the main disadvantage of an SLR. It doesn't help that the Marc Newson-designed body places form before function. It's simply too uncomfortable in-hand, and design choices like poorly-placed controls and the clumsy rubber compartment cover subtract still further from the enjoyment of shooting with the K-01. For a relatively slight increase in size and weight, we'd much rather shoot with one of the company's well-designed DSLR cameras than the Pentax K-01.